Table Top Ice and Snow Layer
July 23, 2007
On April 8, 2007, in Montreal, Canada, I witnessed this fascinating springtime phenomenon a few feet from my patio door. A lens of meltwater that formed between the table surface and the layer of ice and snow just above behaved like a vacuum, causing strong adhesion of the ice layer to the table surface. Because the water film reduces friction, much like ball bearings do, the layer of ice and snow is slippery in a sideways direction. Still, the suction cup effect or adhesion prevents this intact layer from completely sliding away. Since the sideways movement is so slow, the snow and ice layer doesn't all slide off at once. In the photos, it appears that the adhesion is greater than the pull of gravity. Eventually, though, the weight of the ice overcame the suction force, and the precarious layer fell to the ground. Thanks to my friend, Bob Rondeau, for his help with this.